Method of making a needle board



Nov. 23, 1965 A. M. SMITH 11 3,219,732

METHOD OF MAKING A NEEDLE BOARD Original Filed Oct. 4. 1961 5 Sheets-Sheet l INVENTOR.

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Nov. 23, 1965 A. M. SMITH 11 3,219,732

METHOD OF MAKING A NEEDLE BOARD Original Filed Oct. 4, 1961 5 Sheets-Sheet 2 Nov. 23, 1965 A. M. SMITH II 3,219,732

METHOD OF MAKING A NEEDLE BOARD Original Filed Oct. 4. 1961 5 Sheets-Sheet 3 PLACING SHEETS OF MATERIAL TOGETHER FORMING A PLURALITY OF HOLES IN SHEETS FOR DESIRED PATTERN FIG.6

SEPARATING SHEETS TO DESIRED THICKNESS OF NEEDLE BOARD 8I INSERTING NEEDLES IN HOLES ADJUSTING SHEETS TO ORIENT ALL NEEDLES TO DESIRED ANGLE PLACING A SUFFICIENT AMOUNT OF ExPAN SIBLE REsIN IN sPAcE BETWEEN SHEETS TO FILL SPACE WHEN EXPANDED AND THEN EXPANDING THE REsIN IN SITU TO FORM RIGID FOAM REsIN MENTOR ATTORNEYS NOV. 23, 1965 SMITH 3,219,732

METHOD OF MAKING A NEEDLE BOARD Original Filed 001,. 4. 1961 5 Sheets-Sheet 4 SPACING APART SHEETS HAVING IDENTICAL PATTERN OF HOLES THEREIN COATING OPPOSED SURFACES OF SHEETS WITH LUBRICANT FIG.7

IN SERTI N G NEEDLES THROUGH HOLES IN SHEETS ADJUSTIN G SHEETS TO ORIENT ALL NEEDLES TO DESIRED ANGLE PLACING A SUFFICIENT AMOUNT OF EXPANSIBLE RESIN IN SPACE BETWEEN SHEETS TO FILL SPACE WHEN EXPANDED AND THEN EXPANDING THE RESIN IN SITU TO FORM RIGID FOAM RESIN REMOVING NEEDLES FROM SHEETS AND RIGID FOAM RESIN FROM BETWEEN SHEETS REINSERTING NEEDLES INTO INVENTOR FORMED HOLES IN RIGID FOAM RESIN Nov. 23, 1965 A. M. SMiTH 11 3,219,732

METHOD OF MAKING A NEEDLE BOARD Original Filed Oct. 4. 1961 5 Sheets-Sheet 5 SPACI N G APART SHEETS HAVING IDENTICAL PATTERN OF HOLES THERIN FIG. 8

INSERTING NEEDLES THROUGH HOLES ADJUSTING SHEETS TO ORIENT ALL NEEDLES TO DESIRED ANGLE FIXING FRAME ABOUT THE PERIPHERY OF ADJUSTED SHEETS I NVENT OR ATTORNEYS United States Patent Ofiice K 3,219,732 Patented Nov. 23, 1965 3,219,732 METHOD OF MAKING A NEEDLE BDARD Alexander M. Smith II, Elkin, N.C., assignor, by mesne assignments, to The Fiberwoven Corporation, Elkin,

N.C., a corporation of North Carolina Original application Oct. 4, 1961, Ser. No. 142,949, new

Patent No. 3,122,815, dated lvlar. 3, 1964. Divided and this application June 20, 1963, Ser. No. 294,213

17 tilaims. (Cl. 264-45) This application is a division of my co-pending application Serial No. 142,949 filed October 4, 1961, now U.S. Patent No. 3,122,815 issued March 3, 1964, and is entitled to the filing date thereof.

The present invention relates to an improvement in a method of making needle boards for needle looms or the like.

In recent years and, particularly with the advent of synthetic fibers, there has been considerable development in the art of producing non-woven fabrics from batts or webs of loosely matted fibers. Needle looms have been heretofore used to orient the fibers of the webs, the needle looms being provided with needle boards having an array of needles which are reciprocated into and out of the batt or web. Usually there is subsequent treatment to the butt with suitable bonding agents to bond the fibers together.

In my copending application Serial No. 31,910, filed May 26, 1960, and entitled Method of Needle Punching Fibers to Make Needled Fabrics or the Like, now U.S. Patent No. 3,090,100, issued May 21, 1963, there is disclosed an improved needle loom for orienting the fibers of a web of loosely matted fibers into controlled cohering fiber entanglement such as interlacing and interlooping. As disclosed in the aforementioned patent, by having the needles of the array of needles of the needle board adapted to penetrate the web at specific desired angles, it has been found that control of the interlooping and interlacing of fibers can be effectively accomplished.

Heretofore, needle looms employed wooden or metal needle boards or slotted strips for holding shanks of an array of needles in a desired pattern. Special selected mahogany has been considered the best type of material for making needle boards, the mahogany having a thickness in the order of three-fourths of an inch to one inch. The holes for receiving the needle shanks in the wooden or metal boards have been made by utilizing small drills, but such drills often led away from a desired course when drilling through the thick metal or wood board. This was not critical in past needling operations and very little attention was directed to having every needle of the board accurately oriented with respect to every other needle in the board. With the advent of synthetic fibers which led to the discovery that all needles in a pattern of needles must be accurately oriented with respect to each other to provide for controlled needling, the use of the thick wooden or metal boards has been found to be unsatisfactory for accurately holding the shanks of the needles so that the needles have accurate orientation for a desired type of needling.

An object of the present invention is to provide an improved method of making a needle board of a composite structure and capable of holding an array of needles in accurate alignment and orientation.

Still another object of the present invention is to provide an improved method of making a needle board whereby needle alignment and orientation for an array of needles is simultaneously accomplished.

A further object of the present invention is to provide an improved method of making a needle board, of lightweight, sturdy construcn'on and capable of withstanding stresses and strains encountered in continued use of the same.

Another object of the present invention is to provide an improved method of making a needle board wherein the board is made from composite parts and the forming of holes in such parts is accomplished in a manner to provide for accurate orientation of an array of needles.

Ancillary to the preceding object, it is a further object of the present invention to provide a method of making a needle board wherein the holes for receiving the needle shanks in a desired pattern are simultaneously made.

These and other objects of the present invention will appear more fully from the following drawings wherein:

FIGURE 1 is a fragmentary sectional view illustrating the first step in making the needle board of the present invention;

FIGURE 2 is a fragmentary sectional view through a needle board made in accordance with the present invention;

FIGURE 3 is a fragmentary perspective view illustrating a completed needle board for a needle loom with a few of the needles inserted through the holes in the needle board and others omitted for the purpose of clarity;

FIGURE 4 is a fragmentary sectional view illustrating a modified method of making a needle board according to the present invention; and

FIGURE 5 is a fragmentary sectional view of a needle board made in accordance with the method illustrated in FIGURE 4.

FIGURES 6 through 8, inclusive, represent flow diagrams of methods of making the needle boards of the present invention as described in the specification.

Referring now to the drawings wherein like character or reference numerals represent like or similar parts and, more specifically, to the perspective illustration of FIG URE 3, the needle board of the present invention is identified by the numeral 10 and is a rectangular parallelepiped shaped member having a plurality of rows of holes 12 therein for receiving shanks 14 of needles 16. While the needle board shown in FIGURE 3 has a plurality of rows of needles 16 extending transversely of the needle board 10, with the rows of needles aligned with needles in other rows, it is, of course, within the scope of the present invention to arrange the pattern of needles in a manner disclosed in my aforementioned U.S. Patent No. 3,090,100 wherein the transverse rows of needles are staggered with respect to each other so that there may be more needles punching the web transversely of the same in-each widthwise inch. By staggering the rows of needles to obtain more punching per widthwise inch, the needles in a row may be spaced further apart. Any other desired pattern for the array of needles 16 may be used, it being understood the invention pertains to the alignment and orientation of needles in the making of the needle board.

The needle boards of the present invention have an overall width of approximately 8 to 15 inches and anoverall length of approximately 60 to inches. Such needle boards usually contain approximately 2500 to 7000 needles, the needle boards being supported in the needle looms on the ends of oscillating arms or other suitable oscillating structure. The weight or mass of the needle board is of considerable importance because it determines the magnitude of the force required to effect the acceleration and deceleration of high speed oscillation. By lightening the needle board, acceleration forces are reduced; power requirements, various structural stresses and bearing loads are correspondingly reduced. It is also necessary to maintain strength and rigidity in the needle board because of its tremendous size. It will be understood that such needle boards are used for producing continuous lengths of non-woven fabrics having Widths of approximately 60 to 160 inches.

The needle board 10 of the present invention is made by placing two thin sheets of material 18 and 20 to- 3 gether as shown in FIGURE 1. The two thin sheets of material 18 and 20 have an overall size substantially equal to the desired size of the needle board but have a thickness in the range of .020 to .062 inch. The sheets of material 18 and 20 are relatively stiif and may be made from either plastics, such as fiberglass reinforced epoxy resins, or metal, such as thin sheets of aluminum. While FIGURE 1 shows the sheets 18 and 20 spaced apart slightly, this is done merely for the purpose of illustration. The sheets are originally placed together and suitably clamped in a contiguous relationship with one another and then a drilling apparatus comprising one or more drills 22 is used to simultaneously drill through both sheets to form the small holes 24. If a single drill 22 is used, a suitable template may be used to mark the topmost sheet where the holes are to be drilled, the template having a desired pattern for the array of needles. On the other hand, the drilling apparatus may incorporate a plurality of drills arranged in the desired pattern and, if this is the case, then a plurality of holes may be drilled through both sheets of material 18 and 20 simultaneously. It will be appreciated that the sheets 18 and 20 are quite large and there are a great number of holes 24 drilled therein. The drilling apparatus containing a plurality of drills arranged in the desired pattern may be used to drill a portion of the total number of holes to be drilled, it being understood that the sheets could be suitably advanced relatively to the drilling apparatus to repeat the pattern of drilling over the entire area of the sheets.

By holding the thin sheets of material 18 and 20 together in contiguous relationship and drilling through both sheets simultaneously, the exact same pattern of holes 24 is made on both the upper sheet 18 and the lower sheet 20. Since the sheets of material 18 and 24 have a thickness in the order of .020 to .062 of an inch, the drilling operation is accurate because the drills do not have a chance of going off course as the mass through which they are drilling is quite small. The holes 24 drilled into the sheets 18 and 20 have an axis perpendicular to the plane of the sheets and a diameter for receiving the shanks 14 of needles 16.

After the holes 24 have been provided in the sheets 18 and 20, the sheets are separated and the needles 16 are inserted through the holes 24 of the upper sheet 18 as well as the corresponding holes 24 of the lower sheet 20. The needles 16, which are conventional, usually include the shank portion 14, a body portion 26 of reduced diameter having a pointed end 27 and a plurality of barbs thereon (not shown). The shank portion 14 is provided with a securing element or ear 28 which is bent substantially at right angles to the axis of the shank portion.

Once all of the needles 16 have been inserted through their corresponding holes 24 in the upper and lower sheet members 18 and 20, and the sheet members have been spaced apart a distance substantially equal to the desired thickness of the finished needle board, one sheet member is moved or slipped relative to the other sheet member in a plane parallel of the other sheet member and all of the needles are simultaneously oriented and aligned to a desired position. Of course, if it is desired to have all of the needles perpendicular to the surfaces of the sheet members, then the sheet members are adjusted relative one another so that the axes of their respective holes are aligned. On the other hand, if it is desired to have some needles extending at different angles to other needles, the sheet members may be arranged angularly with respect to one another. When the one sheet member 18 has been moved relative to the other sheet member 20 a predetermined distance to obtain a predetermined angular relationship of the needles 16 to the sheet members, then the sheet members 18 and 20 are secured to a frame generally indicated at 30 about their peripheral edges. In more detail, the frame 30 may include a plurality of channel-shaped elements 32 having their legs 34 riveted to the peripheral edges of the sheets 18 and 20, as indicated at 36. While the channel-shaped members 32 have been shown riveted to the sheets 18 and 20, it is, of course, within the scope of the present invention that other means of securing the sheets to the frame 30 may be accomplished such as, for example, gluing, welding, soldering or the like.

The needle board 10 may be reinforced across its Width or length by suitable internal stringers (not shown) either U-shaped or I-shaped in cross section, the stringers being positioned between the sheets and secured thereto after the sheets have been moved relative one another to align and orient the needles but prior to securing the outer frame 30. The internal stringers would, of course, be positioned between the sheets in such a manner that they would not interfere with the needles when the needles were subsequently placed in the holes 24.

After the frame 30 has been secured and all of the needles 16 positioned in the holes 24, the needle board is then ready for use in a needle loom. The needle board 10 is secured to a conventional clamping member 40 shown in broken lines in FIGURES 2 and 3. The clamping member 40 suitably supports the needle board 10 and also bears upon the securing elements or ears 28 of the needles 16 so that they cannot be displaced along their longitudinal axis when the loom is operating. When a needle breaks or becomes worn, the needle board 10 is released from the clamping member 40 and the broken or worn needle is then easily slipped from the holes 24 in the sheets 18 and 20 and replaced by a new needle.

Another preferred form of reinforcing the needle board 10 and making it more rigid is shown in FIGURE 2 wherein the void or space between the plates 18 and 20 is filled with an expansible resin which is expanded in situ to form a rigid foam resin 42. This is accomplished by filling the space between the sheets 18 and 20 with a suitable amount of the expansible resin after the sheets have been spaced apart and adjusted relative one another to orient and align the needles. The frame 30 is secured to the peripheral edges of the sheets 18 and 20 with the resin in the space therebetween and then the composite structure with the needles in place is heated to cause the resin to expand about the shanks of the needles and completely fill the void between the plates and the frame. The resin is cured until it becomes solidified and then the needle board is cooled. The needle board is then ready for use in the needle loom. The needles which were positioned in the holes 24 of the sheets 18 and 20 at the time the resin was expanded and solidified and which had their shank lubricated by a silicone lubricant may be removed from the needle board if it is desired to replace the same by merely pulling the needles out by the ears 28. The needles cause a hole 44 to be molded into the needle board and, of course, when a new needle replaces the old needle, the hole 44 helps to rigidly support the shank 14 of the new needle 16.

Rigid foam resins which have proven satisfactory for the process of making the needle board according to the present invention are epoxy resins, polyurethane resins and polystyrene resins. When an epoxy resin is used, e.g., a bisphenol x-epic'hlorhydrin resin, a powder of the epoxy resin is put into the space between the sheets as mentioned above and then heat is applied to the structure to cause the powder to liquefy and expand. The expansion takes place because the resin has a blowing agent therein which reacts under heat to release a gas. After the epoxy resin has expanded and filled the void or cavity, it is cured by the application of continued heat to cause it to solidify and then the structure is cooled. When rigid polyurethane is employed, it is usually formed from two liquids, one being the urethane prepolymer, e.g., the prepolymer from glycerine-propy-lene oxide adduct (molecular weight 1000) with a 10% excess of toluene dissocyanate, and the other being water (containing a small .5 amount of polydimethyl siloxanes and N-methyl morpholine as conventional surfactant and catalyst). Upon mixing the two liquids, a foam forms and rises to fill the cavity with solidified foam. Rigid polystyrene, on the other hand, is formed by placing small expansible spheres of polystyrene, the spheres having a volatile liquid in them which expands to form a gas when heated and which, as it is liberated, forms a porous expanded polystyrene structure.

While the above-mentioned rigid foam resins are preferable, it is, of course, within the scope of the invention to use other rigid foam resins.

Referring now to FIGURES 4 and 5, a modified form of the present invention is disclosed. In this form of the invention, the needle board is made only of a rigid foam resin such as the aforementioned epoxy resins, polyurethane resins or polystyrene resins. In FIGURE 4, sheets 18' and 20' are provided with holes 24 in an identical manner to the hole 24 of the heretofore described sheets 18 and 20, the sheets 18" and 20' defining a portion of a mold for the needle board 10. The sheets 18' and 20' are then spaced apart a desired distance and needles 16 are inserted through the corresponding holes 24' in the respective sheets. After the array of needles have been inserted, the sheets 18 and 20 are moved relative to each other to orient and align the needles as heretofore described. Then side members 32' forming the sides of the mold are placed around the peripheral edges of the sheets and temporarily secured thereto. The internal surfaces 50 of the sheets 18' and 20 as well as the internal surfaces 52 of the side members 32 are coated with a silicone lubricant, e.g., polydimethylsiloxane. A suitable amount of the foam resin is placed in the cavity of the mold and then the mold is subjected to heat to cause the resin to expand and solidify. After the resin has solidified and prior to disassembly of the mold, all of the needles 16 are removed leaving holes 56in the rigid foam resin needle board 10', the holes having their axes properly oriented and aligned. Once the needles have been removed from the mold, the mold may be disassem' bled by removing the side members 32 and the sheets 18' and 20. The silicone lubricant prevents the sheets 18 and 20 as well as the side members 32' from sticking to the formed needle board 10'. It may also be desirable to coat the shanks of the needles with the silicone lubricant so they can be removed easily.

As shown in FIGURE 5, the needles 16 are then reinserted through the holes 56 in the needle board 10 and the needle board is then clamped to the conventional clamping member 40 of the needle loom.

It will now be seen that the needle board and the method of making the same accomplishes the objects and advantages as heretofore described. While a preferred needle board and method of making same are illustrated and described, the needle board and method of making the same are susceptible to some changes and modifications without departing from the spirit or scope of the invention. Therefore, the terminology in this specification is for the purpose of description and not limitation, the scope of the invention being defined in the claims.

What is claimed is:

1. A method of making a needle board for a needle loom comprising the steps of: placing together two thin sheets of material having an overall plan size of the desired needle board; forming a plurality of holes through the two sheets while held together, the holes being arranged in a desired pattern; separating the two sheets of material by a distance substantially equal to the desired thickness of the needle board and inserting needles through the corresponding holes in the two sheets of material; then adjusting one sheet of material relative to the other sheet of material to simultaneously orient all of the needles to desired angles; placing a sufficient amount of an expansible resin in the space between the sheets of material for filling the same when expanded; and expanding the resin in situ to form a rigid foam resin.

6 2. The method of claim 1 wherein the adjustment is made by moving one sheet parallel to the other sheet.

3. The method of claim 1 wherein the adjustment is made by moving one sheet to an angle relative the other sheet.

4. The method of claim 1 wherein adjustment of one sheet with respect to the other orients all needles perpendicular to the planes of the sheets.

5. The method of claim 1 wherein the expansible resin is an epoxy resin and wherein the expanding of the resin in situ is acomplished by heating to liquefy and expand the same and curing is accomplished by maintaining the heat until the epoxy resin solidifies.

6. The method of claim 1 wherein the expansible resin is a polyurethane resin and wherein the expanding of the resin in situ is accomplished by heating to expand and solidify the same.

7. The method of claim 1 wherein the expansible resin is a polystyrene resin and wherein the expending of the resin in situ is accomplished by heating the resin to release gas therein and expand the same, the heat being maintained until a porous expanded structure is obtained.

8. A method of making a needle board for a needle loom comprising the steps of: placing together two thin sheets of relatively stiff material having a thickness in the range of .020 to .062 inch, the sheets of material having an overall plan size of the desired needle board; drilling a plurality of holes through the two sheets While held together to form a desired pattern of holes for a desired arrangement of needles; separating the two sheets of material by a distance substantially equal to the desired thickness of the needle board and inserting needles through the corresponding holes in the two sheets of material; then adjusting one sheet of material relative to the other sheet of material to simultaneously orient all needles to a desired angle; placing a sufficient amount of an expansible resin in the space between the sheets of material for filling the same when expanded; and expanding the resin in situ to form a rigid foam resin.

9. The method of claim 8 wherein the drilling of the plurality of holes is accomplished by simultaneously drilling the desired pattern of holes through the two sheets of material.

10. The method of claim 8 including the step affixing a frame about the peripheral edges of the two sheets of material after the two sheets of material have been separated and adjusted relative to one another.

11. A method of making a needle board for a needle loom comprising the steps .of: placing together two stiff thin sheets of material having a thickness in the range of .020 to .062 inch and an overall plan size of the desired needle board; forming a plurality of holes through the two sheets of material while held together, the holes being arranged in a desired pattern for a desired arrangement of needles, separating the two sheets of material by a distance substantially equal to the desired thickness of the needle board and inserting needles through the corresponding holes in the two sheets of material; then moving one sheet of material parallel to the other sheet of material to simultaneously orient all needles to a desired angle; and then affixing a frame about the peripheral edges of the two sheets of material to maintain the two sheets of mlalterial in spaced apart and fixed relationship to one anot er.

12. The method of claim 11 including placing a sulficient amount of an expansible resin in the space between the sheets of material for filling the same when expanded; and expanding the resin in situ to form a rigid foam resin.

13. A method of making a needle board for a needle loom comprising the steps of: spacing apart two sheets of material each having an identical pattern of holes therethrough; coating the opposed surfaces of the two sheets of material with a silicone lubricant; inserting needles through corresponding holes in the two sheets of material; adjusting one sheet of material relative to the other sheet of material to simultaneously orient all needles to desired angles; placing a sufiicient amount of an expansible resin in the space between the sheets of material for filling the same when expanded; expanding the resin in situ to form a rigid foam resin; removing the needles from the sheets of material and the rigid foam resin between the sheets of material; removing the sheets of material from the rigid foam resin; and reinserting the needles into holes formed in the rigid foam resin.

14. The method of claim 13 including the steps of forming the pattern of holes by placing the two sheets of material together and drilling the holes through the two sheets in the desired pattern while the two sheets are held together.

15. The method of claim 13 wherein the silicone lubricant is polydimethylsiloxane.

16. The method of making a needle board for a needle loam comprising the steps of: spacing apart two sheets of material each having an identical pattern of holes therethrough; inserting needles through the corresponding holes in the two sheets of material; moving one sheet of material parallel to the other sheet of material to simultaneously orient all needles to a desired angle; and then affixing a frame about the peripheral edges of the two sheets of material to maintain the two sheets of material in spaced apart and fixed relationship to one another.

17. The method of claim 11 including placing a suflicient amount of an expansible resin in the space between the two sheets of material for filling the same when expanded; and expanding the resin in situ to form a rigid foam resin.

References Cited by the Examiner UNITED STATES PATENTS 1,608,727 11/1926 Dickey 264-45 XR 2,663,065 12/1953 Dinham 284 2,680,276 6/ 1954 Filangeri. 2,762,739 9/1956 Weiss 26445 XR 2,806,812 9/1957 Merz 264-45 XR 2,950,495 8/1960 Stingley 264-45 XR ALEXANDER H. BRODMERKEL, Primary Examiner. 

1. A METHOD OF MAKING A NEEDLE BOARD FOR A NEEDLE LOOM COMPRISING THE STEPS OF: PLACING TOGETHER TWO THIN SHEETS OF MATERIAL HAVING AN OVERALL PLAN SIZE OF THE DESIRED NEEDLE BOARD; FORMING A PLURALITY OF HOLES THROUGH THE TWO SHEETS WHILE HELD TOGETHER, THE HOLES BEING ARRANGED IN A DESIRED PATTERN; SEPARATING THE TWO SHEETS OF MATERIAL BY A DISTANCE SUBSTANTIALLY EQUAL TO THE DESIRED THICKNESS OF THE NEEDLE BOARD AND INSERTING NEEDLES THROUGH THE CORRESPONDING HOLES IN THE TWO SHEETS OF MATERIAL; THEN ADJUSTING ONE SHEET OF MATERIAL RELATIVE TO THE OTHER SHEET OF MATERIAL TO SIMULTANEOUSLY ORIENT ALL OF THE NEEDLES TO DESIRED ANGLES; PLACING A SUFFICIENT AMOUNT OF AN EXPANSIBLE RESIN IN THE SPACE BETWEEN THE SHEETS OF MATERIAL FOR FILLING THE SAME WHEN EXPANDED; AND EXPANDING THE RESIN IN SITU TO FORM A RIGID FOAM RESIN. 